I'm currently working on a CCM driver for a i.MX7 board. My reference documentation if the refman Rev 0.1 and Linux source code, especially ./arch/arm/mach-imx/clk-imx7d.c from the Toradex SDK I got.
In the table: 5-11, Clock Root Table, we can see that ARM_A7_CLK_ROOT is plugged to ARM_PLL and AUDIO_PLL.
In the Clock Tree (figure 5.2.4) we can see multiple "orange box" divisor /2, especially between ARM_PLL / ARM_PLL_CLK and AUDIO/VIDEO_PLL and AUDIO/VIDEO_PLL_CLK, and then that ARM_A7_CLK_ROOT is using the PLL values divided by 2.
Linux source code makes no mention of these /2 between PLL and CLK_ROOT.
Can someone clarify what these /2 boxes are and if we have to take them into account when computing CLK_ROOT frequencies ?